Regulators should do anything but "take it easy" on Bitcoin startups. Bitcoin has proven to be in practical terms one of the most risky potentially legitimate investment classes known to man. I'm not discussing its potential use as a currency because it's in fact so risky that it hasn't even made it there yet. All of this means that regulators should be forcing Bitcoin startups to justify themselves.
I have proposed a bill to amend 18 U.S.C. § 1960 that I think would be a step in the right direction:
http://www.plainsite.org/issues/index.html?id=2
I think the notion of a proportionally and increasingly scaled premium paid to an FDIC-style insure is the right way to go (bigger institutions put slightly more in per dollar held in trust to account for systemic risk), but if you handle Bitcoin? Multiply the premium times 30.